2     Routines to set PC methods and options.
10    Contains the list of registered PC routines
15   PCSetType - Builds `PC` for a particular preconditioner type
20 + pc   - the preconditioner context
24 . -pc_type <type> - Sets `PC` type
28   then set the `PC` type from the options database rather than by using
46 PetscErrorCode PCSetType(PC pc, PCType type)  in PCSetType()  argument
49   PetscErrorCode (*r)(PC);  in PCSetType()
52   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCSetType()
55   PetscCall(PetscObjectTypeCompare((PetscObject)pc, type, &match));  in PCSetType()
59 …PetscCheck(r, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unable to find reques…  in PCSetType()
60   /* Destroy the previous private PC context */  in PCSetType()
61   PetscTryTypeMethod(pc, destroy);  in PCSetType()
63   PetscCall(PetscFunctionListDestroy(&((PetscObject)pc)->qlist));  in PCSetType()
65   PetscCall(PetscMemzero(pc->ops, sizeof(struct _PCOps)));  in PCSetType()
67   pc->modifysubmatrices  = NULL;  in PCSetType()
68   pc->modifysubmatricesP = NULL;  in PCSetType()
70   pc->setupcalled = PETSC_FALSE;  in PCSetType()
72   PetscCall(PetscObjectChangeTypeName((PetscObject)pc, type));  in PCSetType()
73   PetscCall((*r)(pc));  in PCSetType()
78   PCGetType - Gets the `PCType` (as a string) from the `PC`
84 . pc - the preconditioner context
91 .seealso: [](ch_ksp), `PC`, `PCType`, `PCSetType()`
93 PetscErrorCode PCGetType(PC pc, PCType *type)  in PCGetType()  argument
96   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCGetType()
98   *type = ((PetscObject)pc)->type_name;  in PCGetType()
102 PETSC_INTERN PetscErrorCode PCGetDefaultType_Private(PC, const char *[]);
105   PCSetFromOptions - Sets `PC` options from the options database.
110 . pc - the preconditioner context
123 .seealso: [](ch_ksp), `PC`, `PCSetType()`, `PCType`, `KSPSetFromOptions()`
125 PetscErrorCode PCSetFromOptions(PC pc)  in PCSetFromOptions()  argument
132   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCSetFromOptions()
135   if (!((PetscObject)pc)->type_name) {  in PCSetFromOptions()
136     PetscCall(PCGetDefaultType_Private(pc, &def));  in PCSetFromOptions()
138     def = ((PetscObject)pc)->type_name;  in PCSetFromOptions()
140   PetscObjectOptionsBegin((PetscObject)pc);  in PCSetFromOptions()
144     PetscCall(PCSetType(pc, type));  in PCSetFromOptions()
145   } else if (!((PetscObject)pc)->type_name && def) {  in PCSetFromOptions()
146     PetscCall(PCSetType(pc, def));  in PCSetFromOptions()
149   PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCNONE, &flg));  in PCSetFromOptions()
152 …) to define preconditioner in nested inner solves", "PCSetUseAmat", pc->useAmat, &pc->useAmat, NUL…  in PCSetFromOptions()
154   PetscTryTypeMethod(pc, setfromoptions, PetscOptionsObject);  in PCSetFromOptions()
158   PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)pc, PetscOptionsObject));  in PCSetFromOptions()
160   pc->setfromoptionscalled++;  in PCSetFromOptions()
170 + pc - the preconditioner context
182 .seealso: [](ch_ksp), `PC`, `DM`, `PCGetDM()`, `KSPSetDM()`, `KSPGetDM()`, `SNESSetDM()`, `TSSetDM(…
184 PetscErrorCode PCSetDM(PC pc, DM dm)  in PCSetDM()  argument
187   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCSetDM()
189   PetscCall(DMDestroy(&pc->dm));  in PCSetDM()
190   pc->dm = dm;  in PCSetDM()
200 . pc - the preconditioner context
207 .seealso: [](ch_ksp), `PC`, `DM`, `PCSetDM()`, `KSPSetDM()`, `KSPGetDM()`
209 PetscErrorCode PCGetDM(PC pc, DM *dm)  in PCGetDM()  argument
212   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCGetDM()
213   *dm = pc->dm;  in PCGetDM()
223 + pc  - the `PC` context
233 .seealso: [](ch_ksp), `PC`, `PCGetApplicationContext()`, `KSPSetApplicationContext()`, `KSPGetAppli…
235 PetscErrorCode PCSetApplicationContext(PC pc, PetscCtx ctx)  in PCSetApplicationContext()  argument
238   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCSetApplicationContext()
239   pc->ctx = ctx;  in PCSetApplicationContext()
249 . pc - `PC` context
262 .seealso: [](ch_ksp), `PC`, `PCSetApplicationContext()`, `KSPSetApplicationContext()`, `KSPGetAppli…
264 PetscErrorCode PCGetApplicationContext(PC pc, PetscCtxRt ctx)  in PCGetApplicationContext()  argument
267   PetscValidHeaderSpecific(pc, PC_CLASSID, 1);  in PCGetApplicationContext()
268   *(void **)ctx = pc->ctx;  in PCGetApplicationContext()